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bioRxiv · 10.1101/2021.03.03.433715

Functional interdependence of the actin nucleator Cobl and Cobl-like in dendritic arbor development

Izadi, M.·Seemann, E.·Schlobinski, D.·Schwintzer, L.·Qualmann, B.·Kessels, M. M.
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Abstract

Local actin filament formation is indispensable for development of the dendritic arbor of neurons. We show that, surprisingly, the action of single actin filament-promoting factors was insufficient for powering dendritogenesis. Instead, this process required the actin nucleator Cobl and its only evolutionary distant ancestor Cobl-like acting interdependently. This coordination between Cobl-like and Cobl was achieved by physical linkage by syndapin I. Syndapin I formed nanodomains at convex plasma membrane areas at the base of protrusive structures and interacted with three motifs in Cobl-like, one of which was Ca2+/calmodulin-regulated. Consistently, syndapin I, Cobl-likes newly identified N terminal calmodulin-binding site and the single Ca2+/calmodulin-responsive syndapin-binding motif all were critical for Cobl-likes functions. In dendritic arbor development, local Ca2+/CaM-controlled actin dynamics thus relies on regulated and physically coordinated interactions of different F-actin formation-promoting factors and only together they have the power to bring about the sophisticated neuronal morphologies required for neuronal network formation.

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Izadi, M., Seemann, E., Schlobinski, D., Schwintzer, L., Qualmann, B., Kessels, M. M.. 2021-03-03. Functional interdependence of the actin nucleator Cobl and Cobl-like in dendritic arbor development. https://doi.org/10.1101/2021.03.03.433715

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